Siskiyou County supervisors have often criticized government regulations and water studies for not taking into account the effects of upland forests on surface flows in local rivers. At their meeting on Tuesday, April 16, they unanimously chose to contribute $10,000 to a study that might provide some insight into those effects.

The agenda item was requested by District 5 Supervisor Marcia Armstrong and District 3 Supervisor Michael Kobseff. The specific focus of the study is evaporative transpiration (the amount of water lost through evaporation and vegetative use) of precipitation in local forests.

As county government continues to struggle through litigation and regulatory challenges over local water issues, the concept of “base flow” (the amount of water in a stream as measured before any human extraction) continues to be a point of controversy as it is an essential part of water models used to study the needs of fish and the impacts of agriculture. Armstrong and Kobseff have argued that many assumptions and calculations about agricultural water use are inaccurate because they are built on allegedly incorrect base flow estimates that do not accurately represent current forest conditions.

Retired U.S. Forest Service district ranger Ray Haupt is the project director for the proposed study. He submitted an outline of the study and answered the board’s questions.

The project outline states, “This is a localized vegetation and hydrologic look at what happens to precipitation in Mediterranean climates once it reaches the Earth’s surface.” The study will be confined to the Sugar Creek watershed, a tributary to the Scott River between the towns of Etna and Callahan. The Sugar Creek watershed has been chosen because it has a long history of vegetative data, long-term photographic records, long-term weather data and “is small enough with minimal human development, which facilitates good research requirements” according to the outline.

Haupt said the study will partner with the Northern California Resource Center, the University of California, Berkeley and Merced, the U.S. Forest Service and the timber land investment company Timbervest.

“We’re concerned with the amount of water available for stream flow and groundwater recharge, not the downstream use or the timing of it,” Haupt said. “We want to understand the input to the system before you go about doing other studies below that may quantify use.” He said the proposed study will model the loss of water through evaporation and transpiration to better understand how much of the precipitation input is lost before it finds its way into creeks and rivers, thus establishing a base flow estimate.

According to Haupt, forest density has increased over time – partially due to fire suppression – and increased density of forest canopy increases evaporation of precipitation before it can soak into the ground. This is one reason he and others involved in the project feel a need to gather local data in order to understand local watersheds.

Page 2 of 2 - Haupt said many currently available studies on these processes have been done in regions that are significantly different from that of Siskiyou County’s Mediterranean-like climate.

“I firmly believe, since my early years working with the watershed council in Scott River back in the ‘90s, that you can’t cure an issue in an ecosystem unless you understand the limitations on it,” Haupt told the board, adding, “And you must understand the entire ecosystem before you propose cures.”

In Haupt’s opinion, most of the focus in curing Scott Valley water issues, to date, has been confined to activities on the valley floor. He said regulation based on this approach is “at best grasping at straws” and “at worst probably politically driven.” He explained that the total cost of the Sugar Creek study will likely be between $80,000 and $100,000, noting that the project group will be going to “major outside contributors” for additional money. He said the Klamath National Forest has already committed to providing the first $10,000 of funding for the project, which is slated to begin in the fall of 2014.

The board of supervisors voted unanimously to provide the next $10,000, which will likely be taken from the county’s specialized services fund under the natural resources budget.